.top{
    position: fixed;
    background-color: yellow;
    top: 0%;
    width: 100%;
    height: 50px;
    opacity: 80%;
}
.left{
    position: fixed;
    left:1em ;
    background-color: red;
    height: 400px;
    width: 50px;
    top: 5em;
}
.right{
    top: 5em;
    position: fixed;
    right: 1em;
    background-color: red;
    height: 400px;
    width: 50px;
}
.bottom{
    position: fixed;
    bottom: 1em;
    background-color: yellow;
    width: 100%;
    height: 50px;
    opacity: 80%;
}
.zho{
    /*text-align: center;*/
    width: 50px;
    margin: auto;
   
}